Abstract: This invention relates to a stackable file storage carton characterized by an open-front box fitted with an integrally formed access opening cover hingedly attached to the bottom of the box along the front edge of the latter for movement from a closed position into an open one forming an extension of said box bottom. The access opening cover is comprised of a panel sized and shaped to cover the access opening. This panel is bordered along its free edges by upstanding fence-forming flanges cooperating therewith and with one another to define a tray which in open position is adapted to receive and support a file slid forwardly from within the box. The front flange is formed to provide a pocket extending lengthwise thereof which is open at both ends to receive and hold tabs depending from the front edges of the flanges bordering the sides of the cover panel.